White light illumination device and method of manufacturing the same

Abstract

The present invention describes an apparatus and method for manufacturing a white light-emitting diode (LED) using a powder with characteristics of fluorescence to achieve a high-luminosity white LED. The LED emitting ultraviolet light is used as an excitation source, which excites a first powder with blue-green light, and a second powder with orange light. After that, a white light is produced by blending blue-green and orange light with the principle of complementary colors. For achieving the high-luminosity white LED, the invention adopts a suitable LED to be the excitation source with a suitable blending proportion. On the other hand, the implementation of the fluorescent powder with blue-green light can be modulated using a metal ion in the host lattice to change the ligard field of the crystal.

Description

BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The present invention relates to a white light illumination device and a method for producing the same. It particularly relates to a white light illumination device and a method for producing the same that uses two fluorescent materials and an ultraviolet excitation light source to achieve white light with high-luminosity according to the principle of complementary color. [0003] 2. Description of Prior Art [0004] White light is a mixture of multiple colors of light, including at least two kinds of light with different wavelengths. For instance, the viewer can perceive the mixture of red, blue and green light or the mixture of blue and yellow as white light. Therefore, a white light illumination device is attainable according to the principle as above described. [0005] Conventionally, there are many methods of obtaining a white light illumination device. The first conventional method is to use three light emitting di...

AI Technical Summary

Problems solved by technology

However, the conventional methods suffer from the following disadvantages.

White light can no longer be produced if one of the LEDs fails.

Moreover, a different controlling circuit responding to each LED is necessary, which is expensive.

However, the second and the third conventional methods utilize the principle of complementary colors to generate white light, of which the spectrum distribution is not as continuous as that of natural sunlight in the visible portion of the spectrum.

In result, the white light generated by these methods has a lower color saturation, and is only suitable for simple illumination purposes.

Therefore, the above conditions greatly limit number of fluorescent materials that can be utilized, causing difficulties in choosing suitable fluorescent materials.

However, most impurity ions need different excitation wavelengths, so the feasibility of this method is not as high as expected.

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